The objective of the proposed research is to study the effects of glucocorticoids on the structure and function of the calf and human (normal and cataractous) lens as part of an investigation into the mechanism by which these steroids induce posterior subcapsular cataract (PSCC). We have already demonstrated the presence of a glucocorticoid receptor in lens epithelium of the calf by biochemical and radioautographic techniques and have established cloned cell lines from the tissue which contain gamma crystallin. It is our hypothesis that glucocorticoids alter cell differentiation by interfering with the normal sequence of gene transcription. It is planned to continue our studies of the glucocorticoid receptor, receptor related events and the effect of glucocorticoids on cell differentiation from whole homogenates, explants and established cell lines of lens epithelium. In addition, the metabolism of glucocorticoids by lens tissue will be studied.